| Nicolás Peña Moreno | 0a80ac8 | 2019-08-28 17:31:08 | [diff] [blame] | 1 | <!DOCTYPE HTML> |
| 2 | <meta charset=utf-8> |
| 3 | <title>Largest Contentful Paint: observe text with display style.</title> |
| 4 | <body> |
| 5 | <script src="/resources/testharness.js"></script> |
| 6 | <script src="/resources/testharnessreport.js"></script> |
| 7 | <style> |
| 8 | #title { |
| 9 | display: flex; |
| 10 | } |
| 11 | </style> |
| 12 | <h1 id='title'>I am a title!</h1> |
| 13 | <script> |
| 14 | async_test(function (t) { |
| Stephen McGruer | b291cab | 2020-04-16 15:42:28 | [diff] [blame] | 15 | assert_implements(window.LargestContentfulPaint, "LargestContentfulPaint is not implemented"); |
| Nicolás Peña Moreno | 0a80ac8 | 2019-08-28 17:31:08 | [diff] [blame] | 16 | let beforeRender; |
| 17 | /* In this test, we first observe a header with style 'display: flex'. |
| 18 | * Once observed, we remove it and add a header with style 'display: grid'. |
| 19 | * And once that is observed, we remove it and add a header with style 'display: block'. |
| 20 | * At each step, we check the values of the entries received. |
| 21 | */ |
| 22 | let observedFlex = false; |
| 23 | let observedGrid = false; |
| 24 | const observer = new PerformanceObserver( |
| 25 | t.step_func(function(entryList) { |
| 26 | assert_equals(entryList.getEntries().length, 1); |
| 27 | const entry = entryList.getEntries()[0]; |
| 28 | assert_equals(entry.entryType, 'largest-contentful-paint'); |
| 29 | assert_greater_than_equal(entry.renderTime, beforeRender); |
| 30 | assert_greater_than_equal(performance.now(), entry.renderTime); |
| Hao Liu | f23c7ed | 2022-11-30 15:43:32 | [diff] [blame] | 31 | assert_approx_equals(entry.startTime, entry.renderTime, 0.001, |
| 32 | 'startTime should be equal to renderTime to the precision of 1 millisecond.'); |
| Nicolás Peña Moreno | 0a80ac8 | 2019-08-28 17:31:08 | [diff] [blame] | 33 | assert_equals(entry.duration, 0); |
| 34 | // TODO: find a good way to bound text size. |
| 35 | assert_greater_than_equal(entry.size, 500); |
| 36 | assert_equals(entry.url, ''); |
| 37 | assert_equals(entry.loadTime, 0); |
| 38 | if (!observedFlex) { |
| 39 | observedFlex = true; |
| 40 | assert_equals(entry.id, 'title'); |
| 41 | const title = document.getElementById('title'); |
| 42 | assert_equals(entry.element, title); |
| 43 | // Remove 'display: flex' and add 'display: grid' text. |
| 44 | title.parentNode.removeChild(title); |
| 45 | const title2 = document.createElement('h1'); |
| 46 | title2.id = 'title2'; |
| 47 | title2.style = 'display: grid'; |
| 48 | title2.innerHTML = 'I am a second title!'; |
| 49 | document.body.appendChild(title2); |
| 50 | beforeRender = performance.now(); |
| 51 | } else if (!observedGrid) { |
| 52 | observedGrid = true; |
| 53 | assert_equals(entry.id, 'title2'); |
| 54 | const title2 = document.getElementById('title2'); |
| 55 | assert_equals(entry.element, title2); |
| 56 | // Remove 'display: grid' and add 'display: block' text. |
| 57 | title2.parentNode.removeChild(title2); |
| 58 | const title3 = document.createElement('h1'); |
| 59 | title3.id = 'title3'; |
| 60 | title3.style = 'display: block'; |
| 61 | title3.innerHTML = 'I am the third and last title!'; |
| 62 | document.body.appendChild(title3); |
| 63 | beforeRender = performance.now(); |
| 64 | } else { |
| 65 | assert_equals(entry.id, 'title3'); |
| 66 | const title3 = document.getElementById('title3'); |
| 67 | assert_equals(entry.element, title3); |
| 68 | t.done(); |
| 69 | } |
| 70 | }) |
| 71 | ); |
| 72 | observer.observe({type: 'largest-contentful-paint', buffered: true}); |
| 73 | beforeRender = performance.now(); |
| 74 | }, 'Text with display style is observable.'); |
| 75 | </script> |
| 76 | </body> |
